中文摘要：

阿斯喀尔特Be-Nb-Mo矿床位于新疆阿尔泰成矿带,是同时产有花岗岩型和花岗伟晶岩型矿体的稀有金属矿床。为确定该矿床的成矿年龄,采用ICP-MS辉钼矿Re-Os同位素技术,测得白云母钠长石花岗岩带内6件辉钼矿样品的Re-Os等时线年龄为211.9±4.1 Ma,加权平均年龄为214.9±1.2 Ma,表明该矿床形成于燕山早期。同位素精确定年结果暗示阿斯喀尔特矿床上部似伟晶岩成矿带形成的主要机制可能是岩浆液态不混溶作用。

英文摘要：

The Askaerte Be-Nb-Mo deposits,located in Altai orogeny belt of Xinjiang,develop both granite-type and pegmatite-type minerallization. In order to determine the age of mineralization,6 molybdenum-bearing samples on the muscovite-albite granite were selected for precise dating through ICP-MS molybdenite Re- Os isotopic measurement,and yielded isochron age of 211. 9 ± 4. 1 Ma,a weighted average age of 214. 9 ± 1. 2 Ma,indicating that the deposit was formed in the Early Yanshanian. Istope dating suggests that the ore-forming mechanism of the upper pegmatite metalogenic belt of Askaerte may be liquid immiscibility of granitic magma.